| − | The arctangent function is the inverse of the [[tangent]] function. Whereas tangent converts an angle to the ratio of the length of the opposite side of a right triangle to the adjacent one, arctangent is used to find the angle when the ratio is known. | + | The '''arctangent''' function is the inverse of the [[tangent]] function. Whereas tangent converts an angle to the ratio of the length of the opposite side of a right triangle to the adjacent one, arctangent is used to find the angle when the ratio is known. |